1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define TRACE_TAG TRACE_RWX
18 
19 #include "adb_io.h"
20 
21 #include <unistd.h>
22 
23 #include <base/stringprintf.h>
24 
25 #include "adb_trace.h"
26 #include "adb_utils.h"
27 #include "sysdeps.h"
28 
SendProtocolString(int fd,const std::string & s)29 bool SendProtocolString(int fd, const std::string& s) {
30     int length = s.size();
31     if (length > 0xffff) {
32         length = 0xffff;
33     }
34 
35     return WriteFdFmt(fd, "%04x", length) && WriteFdExactly(fd, s);
36 }
37 
SendOkay(int fd)38 bool SendOkay(int fd) {
39     return WriteFdExactly(fd, "OKAY", 4);
40 }
41 
SendFail(int fd,const std::string & reason)42 bool SendFail(int fd, const std::string& reason) {
43     return WriteFdExactly(fd, "FAIL", 4) && SendProtocolString(fd, reason);
44 }
45 
ReadFdExactly(int fd,void * buf,size_t len)46 bool ReadFdExactly(int fd, void* buf, size_t len) {
47     char* p = reinterpret_cast<char*>(buf);
48 
49     size_t len0 = len;
50 
51     D("readx: fd=%d wanted=%zu\n", fd, len);
52     while (len > 0) {
53         int r = adb_read(fd, p, len);
54         if (r > 0) {
55             len -= r;
56             p += r;
57         } else if (r == -1) {
58             D("readx: fd=%d error %d: %s\n", fd, errno, strerror(errno));
59             return false;
60         } else {
61             D("readx: fd=%d disconnected\n", fd);
62             errno = 0;
63             return false;
64         }
65     }
66 
67     D("readx: fd=%d wanted=%zu got=%zu\n", fd, len0, len0 - len);
68     if (ADB_TRACING) {
69         dump_hex(reinterpret_cast<const unsigned char*>(buf), len0);
70     }
71 
72     return true;
73 }
74 
WriteFdExactly(int fd,const void * buf,size_t len)75 bool WriteFdExactly(int fd, const void* buf, size_t len) {
76     const char* p = reinterpret_cast<const char*>(buf);
77     int r;
78 
79     D("writex: fd=%d len=%d: ", fd, (int)len);
80     if (ADB_TRACING) {
81         dump_hex(reinterpret_cast<const unsigned char*>(buf), len);
82     }
83 
84     while (len > 0) {
85         r = adb_write(fd, p, len);
86         if (r == -1) {
87             D("writex: fd=%d error %d: %s\n", fd, errno, strerror(errno));
88             if (errno == EAGAIN) {
89                 adb_sleep_ms(1); // just yield some cpu time
90                 continue;
91             } else if (errno == EPIPE) {
92                 D("writex: fd=%d disconnected\n", fd);
93                 errno = 0;
94                 return false;
95             } else {
96                 return false;
97             }
98         } else {
99             len -= r;
100             p += r;
101         }
102     }
103     return true;
104 }
105 
WriteFdExactly(int fd,const char * str)106 bool WriteFdExactly(int fd, const char* str) {
107     return WriteFdExactly(fd, str, strlen(str));
108 }
109 
WriteFdExactly(int fd,const std::string & str)110 bool WriteFdExactly(int fd, const std::string& str) {
111     return WriteFdExactly(fd, str.c_str(), str.size());
112 }
113 
WriteFdFmt(int fd,const char * fmt,...)114 bool WriteFdFmt(int fd, const char* fmt, ...) {
115     std::string str;
116 
117     va_list ap;
118     va_start(ap, fmt);
119     android::base::StringAppendV(&str, fmt, ap);
120     va_end(ap);
121 
122     return WriteFdExactly(fd, str);
123 }
124